Elastic strand



W. J. FOX

ELASTIC STRAND Nov. 30, 1937.

Filed Feb. 25, 1937 W ZNVENTOR.

JZFO 90 O kw ATTORNI;

Patented Nov. 30, 1937 UNITED STATES PATENT OFFICE ELASTIC STRANDWilliam J. Fox, Philadelphia, Pa., assignor to James R. Kendrick 00.,Inc., Philadelphia, Pa., a corporation of Pennsylvania ApplicationFebruary23, 1937, Serial No. 127,288 a 19 Claims. (Cl. 117-57) Thisinvention relates to improvements in elasrelated to each other that onerubber element tic strands for use in the manufacture of elastic willsubstantially surround and confine the other fabrics of the characteremployed in the manuand prevent the contact of covering threads withfacture of articles of wearing apparel and surgithe inner element andalso protect the same cal appliances. against contact with outside airand moisture 5 Such strands comprise elastic, stretchable ruband therebyprevent the deleterious effects hereber confined within surroundingcovering threads tofore caused by such contacts. I which extend spirallyaround the rubber in a The invention resides in the elements and thmanner to permit the strand as a whole to be combinations of them in theimproved strand,

stretched longitudinally and to return to its as will be hereinafterdescribedand claimed. 10

condition before it was stretched. In the accompanying drawing,illustrating the The elastic fabrics in which such strands areinvention, used comprise the strands and binding threads Figure 1 is aside view of an elastic strand,

therefor, the strands being arranged side by side greatly enlarged,constructed in accordance with and the binding threads cooperating withthe the invention, showing in the region of the line 15 strands to formthe fabrics and retain the strands 2--2 the appear of the completeStrand,

therein in a manner 'to permit the fabrics in showing in the region ofthe line 3-3 the aptheir entireties to be stretched in directionslonpearance of the strand after the removal of the gitudinally of thestrands. outer covering threads, showing in the region When the elasticfabrics are subjected to sewof the line 4-4 the appearance of the stranding operations, it frequently happens that the after the removal of theinner covering threads,

sewing needle penetrates the rubber of some of and showing in the re ofthe line the the strands, leaving holes or broken edges thereappearanceof the St after the removal of in, and, at times, leaving the sewingthread exthe Outer and inner covering threads and the tending throughthe rubber; and when any or all Outer rubbe e e e tof these thingsoccur. they often cause breakage Figures 2, n 5 re transverse Sectionsin the impaired rubber of the strands, under the hr u th st and and pats h r f, n l s frequent stretching and releasing of the fabric, and5-5, respective y o and thereby cause impairment-and deterioration 6 s etransverse Section through in the fabric fled form of the strand.

An object of the. invention is to provide an R i g to e drawi e imp ovedand elastic strand of novel and advantageous conp is s an i nt ly l atd. u r elestruction wherein low manufacturing costs are t or e a rubberelement 1 located combined with efliciency in the normal operawardly 0ft e core in er covering th ea s 3 tions of the strands, and wherein theimpairsurroundin the r b elements and 1, nd

ment of the strands and the fabrics, from the outer ve i r a 9surrounding t e inner causes above referred to, and the detrimentalcovering, hreads 8.

effects resulting therefrom, are reduced to a The inner rubber element 0ore 5 s c a minimum. s acterized by being elastic and stretchable; it

Another object is to provide an elastic strand ay be of any known andapprove q y, m

containing two or more rubber elements extende ured in any app e and itmay 40 ing longitudinally withi the covering threads be of a desiredform in cross section. When thereof and possessing differentcharacteristics the i eel'e manufactured by being cut whereby advantagesare gained in the durability from a S eet efsulteble f, the core Will ofthe strand coupled with economy in the manbe normally s u in SS Q u it Wll ufacture thereof. i be deformed into substantially round cross sec-Another object is to provide an elastic strand n y the rubbe e e 1 d t er containing two or more rubber elements extend- 8 covering t a 3 ml inglongitudinally within'the covering threads The ubbe ent 1 s eCharacteristics and having different resistances to stretching, beingelastic and stretchable, and, in its norwhereby the desired resistanceto stretching of al cond tion it is in the rm 01' a flat ribbon thecomplete strand may be economically prowhich may be manufactured underthe known vided. methods in the rubber art. This ribbon is of a Anotherobject isto provide an elastic strand suitable width to enable it to bedeformed transcontaining two rubber elements extending lonversely' tocause it to embrace and-substantially gitudinally within the coveringthreads and so surround the inner core I in contact therewith,

characteristics desired in the complete strand.

As herein illustrated, the inner covering 8 is comprised of two threads,and the outer covering 9 is comprised of four threads. The threads 8 arewrapped spirally around the rubber elements 6 and 1, and the threads 9are wrapped spirally around the rubber elements and the threads 8reversely of the threads 8, as illustrated in the drawing, such wrappingpreventing the strand from twisting and kinking.

In producing the improved strand the rubber ribbon 1 is applied'to therubber core 6, the inner threads 8 are applied to the ribbon 1 and theouter threads 9 are applied to theinner threads 8, in the order named,in a continuous operation, while the rubber elements are maintained in alongitudinally stretched condition in accordance with the character ofthe rubber elements, and in accordance with the result desired in thefinished strand. The threads 8 and 9 are each applied by the usual meansemployed in this art for covering rubber cores, the threads 8 beingapplied in advance of the application of the threads 9; and, when theinner threads are applied, they automatically deform the rubber ribbon Ifrom its normally flat condition and cause it to embrace andsubstantially surround the core 5 inwardly of the threads 8 and incontact with the core. After the application of the threads 8 and 9, andthe release of the rubber elements 6 and 1, such elements contractlongitudinally and expand transversely until they are stopped by thesurrounding threads 8 and 9 which then hold or retain them in astretched condition; and, while the threads 8 and 9 hold the elements 6and 1 in a stretched condition, such condition is far from the limit towhich the elements may be stretched. The greater the extent to which thethreads hold the enclosed rubber elements stretched, the greater will bethe resistance of the elements to further stretching when the completestrand is stretched, and, therefore, it will be understood that thestretch resisting characteristics of the rubber elements will determinethe extent to which it will be necessary for the covering threads 8 and9 to maintain them stretched from their normal lengths, to provide the,desired stretch resistance in the complete strand.

The development in the rubber art has been such that rubber elements foruse in elastic strands in this art are now obtainable which havesuflicient resistance to being stretched from the norinal lengthsthereof as not to be required to be held by the covering threads in astretched condition at all or stretched only to a very little 'orlimited extent. One or more of the rubber elements of my improved strandmay be formed of rubber having such or similar resistance and thecovering threads may enclose such elements in an unstretched conditionin the strand or in a condition in which only one or both of suchelements are held stretched from the normal length thereof.

The expense in obtaining rubber elements for use in elastic strands inthis art varies with the form thereof and the resistance thereof tostretching, and, usually, the expense is greater in the fiat or ribbonform and in the greater resistance to stretching regardless of the form.

My aim is to accomplish the objects of my invention by obtaining thedesired results in the strand, while keeping the expense ofmanufacturing the same well within the bounds of economy. To this end, Ihave obtained good results in the form of embodiment of the inventionherein illustrated, and by the use therein of rubber elements of suchcharacter that by having the rubber core 6 stretched to a length manytimes its normal length and almost to its elastic limit, and by havingthe rubber ribbon I stretched to a lesser extent with relation to itsnormal length during the application of the covering threads 8 and 9thereto, and by having the covering threads related thereto so thatthereafter each three inches of the finished strand will have therein alength of core 6 held by the covering threads stretched from a normallength of approximately one and one-eighth inches, and a length ofribbon I held by the covering threads stretched from a normal length ofapproximately one and threequarters inches. This relationship of theparts provides an elastic strand which will not twist or kink and whichwill have an appropriate resistance to stretching for use in elasticfabrics.

In addition to the foregoing characteristics of my improved strand whichguard against rubber breakage, I provide other means to guard againstsuch breakage by forming the core or element 6 and the ribbon or element1 each of rubber which differs characteristically from the rubber of theother in that the rubber of one element, the core 6 in the presentinstance, offers greater resistance to being stretched than that offeredby the other element, the ribbon I in the present instance; and byrelating the rubber elements to each other and to the covering threadsso that the threads will maintain one element, the core 6 in the presentinstance, stretched from its normal length under a tension which isgreater than the tension of the other element, the ribbon 1 in thepresent instance.

I have discovered that the relations and characteristic differences ofthe parts of the strand as herein shown and described, separately andcollectively considered, materially reduces the breakage of the rubberelements heretofore caused by needle punctures. The relation andcharacteristic diiferences of the rubber elements enables me to providethe desired resistance to stretching in an elastic strand containing tworubber elements one of which is held by the covering threads under lesstension than the other, and, therefore, is less liable to snap or breakafter being punctured by a needle. Should the rubber element held underthe greater tension snap or break, the remaining rubber element will, inmost instances, remain intact and, in a large measure, prevent the otherelement from having pronounced detrimental eficcts.

The use of the two forms of rubber elements 6 and 1, related as hereinshown and described,

enables me to protect the element 6 by the ele- I ment 1, and, at thesame time provide the entire strand with the desired resistance tostretch in an economical manner, because the cost of.

the rubber in the form of the core 6 is less than the cost of the rubberin the form of the ribbon I.

By having the rubber ribbon I embrace or surround the rubber core 6 i1contact therewith,

the core is protected against contact with air and moisture and thedeleterious effects thereof upon the core, and the core 6 is alsoseparated from the covering threads and protected against the chafingaction thereof which would be present if the ribbon 1 were eliminatedand which would cause deterioration of the core and thereby shorten theperiod of its useful service.

In the modification shown in Fig. 6, I employ two rubber ribbons II), IIin lieu of the single ribbon 1, shown in the other figures of thedrawing, and I arrange the two ribbons III, II on opposite sides of thecore 6 and deform them transversely so that they will embrace oppositesides of the core, and I bring their longitudinal edges into closerelationship, so that together they will substantially surround the core6 in contact therewith. In this construction the ribbons in, II willexert the same pull on opposite sides of the strand, and there will beno tendency to kink the same even though the ribbons In, H do not bearthe same relation to the other parts of the strand as that borne by thesingle ribbon I.

I claim:

1. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,rubber ribbon extending longitudinally of the strand; and coveringthreads surrounding said core and said ribbon and transversely deformingthe ribbon into contact with the rubber core.

2. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,rubber ribbon wider than said core and extending longitudinally of thestrand; and covering threads surrounding said core and said ribbon andtransversely deforming the ribbon into contact with the rubber core.

3. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally-of the strand; a stretchable, elastic,rubber ribbon wider than said core and extending longitudinally of thestrand; and covering threads surrounding said core and said ribbon andtransversely deforming the ribbon into embracing contact with the rubbercore.

4. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,rubber covering substantially surrounding said rubber core in contacttherewith; and. covering threads surrounding said rubber covering andsaid core.

5. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,rubber ribbon extending longitudinally of the strand; and coveringthreads surrounding said core and said ribbon and transversely deformingthe ribbon into contact with the rubber core and maintaining the corestretched longitudinally to a length greater than its normal length.

6. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elasticrubber ribbon wider than said core and extending longitudinally of thestrand; and covering threads surrounding said core and said ribbon andtransversely de-' forming the ribbon into contact with the rubber coreand maintaining the core stretched longitudinally to a length greaterthan its normal length.

7. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,

rubber ribbon wider than said core and extending longitudinally of thestrand; and covering threads surrounding saidcore and'said ribbon andtransversely deforming the ribbon into embracing contact with the rubbercore and maintaining said core stretched longitudinally to a lengthgreater than its normal length. g

8. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,rubber covering substantially surrounding said core in contacttherewith; and covering threads surrounding said rubber covering andsaid core and maintaining said core stretched to a length greater thanits normal length.

9. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,rubber ribbon extending longitudinally of the strand; and coveringthreads surrounding said core and said ribbon and transversely deformingthe ribbon into contact with the core and maintaining said core and saidribbon each stretched longitudinally to a length greater than its normallength,

10. An elastic fabric strand comprising a stretchable, elastic rubbercoreextending longitudinally of the strand; a stretchable, elastic,rubber ribbon wider than said core and extending longitudinally of thestrand; and covering threads surrounding said core and said ribbon andtransversely deforming the ribbon into contact with the rubber core andmaintaining said core and said ribbon each stretched longitudinally to alength greater than its normal length.

11. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,rubber ribbon wider than said core and extending longitudinally of thestrand; and covering threads surrounding said core and said ribbon andtransversely deforming the ribbon into embracing contact with the rubbercore and maintaining said core and said ribbon each stretchedlongitudinally, to a length greater than its normal lengths 12. Anelastic fabric strand comprising a stretchable, elastic, rubber coreextending longitudinally of the strand; a stretchable, elastic, rubbercovering substantially surrounding said rubber core in contacttherewith; and covering threads surrounding said rubber covering andsaid core and maintaining them each stretched to a length greater thanits normal length.

13. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,

rubber ribbon extending longitudinally ofthe strand; covering threadssurrounding said core and said ribbon and transversely deforming theribbon into contact with the rubber core and maintaining said core andsaid ribbon each its normal length; and the extent to which the coveringthreads maintain the core stretched from its normal length being greaterthan the extent to which the covering threads maintain the ribbonstretched beyond its normal length.

14. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elastic,rubber ribbon wider than said core and extending longitudinally of thestrand; covering threads surrounding said core and said ribbon andtransversely deforming the ribbon into contactwiththe stretchedlongitudinally to a length greater than rubber core and maintaining saidcore and said ribbon each stretched longitudinally to a length greaterthan its normal length; and the extent to which the covering threadsmaintain the core stretched from its normal length being greater thanthe extent to which the covering threads maintain the ribbon stretchedbeyondits normal length.

15. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally of the strand; a stretchable, elasticrubber ribbon wider than said core and extending longitudinally of thestrand; covering threads surrounding said core and said ribbon andtransversely deforming the ribbon into embracing contact with the rubbercore and maintaining said core and said ribbon each stretchedlongitudinally to 'a length greater than its normal length; and theextent to which the covering threads maintain the core stretched fromits normal length being. greater thanthe extent to which the coveringthreads maintain the ribbon stretched beyond its normal length.

16. An elastic fabric strand comprising a stretchable, elastic, rubbercore extending longitudinally .of the" strand; a stretchable, elastic,

rubber-covering substantially surrounding said rubber core in contacttherewith; covering threads surrounding said rubber covering and saidcore andmaintaining them each stretched to a length greater than itsnormal length; and the extent to which the covering threads maintain thecore stretched from its normal length being greater than the extent towhich the cover ing threads maintain said rubber covering stretchedbeyond its normal length.

17. An elastic fabric strand comprising two stretchable, elastic, rubberelements, and covering threads surrounding said elements, one of saidelements being held by said threads stretched from its normal length andunder a tension greater than the tension of the other element.

18. An elastic fabric strand comprising two stretchable, inindependently movable, elastic,

. the rubber of which one element is formed possessing thecharacteristic of offering greater resistance to stretching than thatofiered by the other element.

WILLIAM J. FOX.

